1. Field of the Invention
The present invention relates to a control method for a novel stepping motor and a novel stepping motor with unipolar or bipolar winding type.
2. Description of the Prior Art
At the transition of a stepping motor from the moving state to the stopped state, the rotor reaches standstill after damping vibration around the target stable point. In order to reduce the period of such damping vibration, it has been proposed to dissipate the kinetic energy of the rotor and to rapidly damp the vibration when the rotor reaches the target stable point by appropriately controlling the energized phase and the energizing time.
However such method is scarcely effective in case the load to the motor varies, and the manner of convergence of vibration fluctuates significantly every time due to the fluctuation in the torque of the motor itself. For this reason, in actual use, the damping time required converging the vibration has to be determined with an ample margin. Consequently a closed loop control for example with an additional position detector has been indispensable for a high-speed operation.